Gemini Deep Deep Survey (GDDS)

The primary goal of the survey is to constrain the space density at high redshift of evolved high-mass galaxies. We obtained 309 spectra in four widely separated 30-arcmin^2^ fields using the Gemini North telescope and the Gemini Multi-Object Spectrograph (GMOS).

The spectra define a one-in-two sparse sample of the reddest and most luminous galaxies near the I-K versus I color-magnitude track mapped out by passively evolving galaxies in the redshift interval 0.8<z<1.8. This sample is augmented by a one-in-seven sparse sample of the remaining high-redshift galaxy population. The GMOS spectrograph was operating in a nod-and-shuffle mode, which enabled us to remove sky contamination with high precision, even for typical exposures times of 20-30hr per field.